Another great resource for the graphics side of running a clothing line is “The Clipping Path.com”
They will provide a clipping path service for any type of image you have. The rates are extremely affordable. I highly recommend checking them out to see their clipping path service options as well as the other design related services that they offer.
One of the most important things to a clothing line is the artwork used. Not only does the artwork need to look nice, it needs to be set up properly for the printing process that will be used. The best way to get your artwork into the correct format is to talk to the printing company that you will be using to print the garments. Different processes will require different file formats. There is a company that will vectorize your artwork for an affordable rate.
They will set your images up for what ever type of printing that you are trying to do. They can also create some custom artwork and do color separations for screenprinting.